<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>3_回调ref中回调执行次数的问题</title>
</head>
<body>
    <!-- 准备好一个“容器” -->
    <div id="test1"></div>
    <!-- 引入react核心库 -->
    <script type="text/javascript" src="../js/react.development.js"></script>
    <!-- 引入react-dom，用于支持react操作DOM -->
    <script type="text/javascript" src="../js/react-dom.development.js"></script>
    <!-- 引入babel，用于将JSX转为JS -->
    <script type="text/javascript" src="../js/babel.min.js"></script>
    <script type="text/babel">
        //创建组件
        class Demo extends React.Component {
            state = {isHot:true}

            showData= () =>{
                console.log(this)
                const{input1} = this
                alert(input1.value)
            }

            changeWeather = () =>{
                const {isHot} = this.state
                this.setState({isHot: !isHot})
            }
            seveInput = (c) =>{
                this.input1 = c;
                console.log(c)
            }

            render(){
                const {isHot} = this.state
                return(
                    <div>
                        <h1>今天天气很{isHot ? '炎热': '凉爽'}</h1>
                        {/*<input ref={(currentNode) =>{this.input1 = currentNode;console.log('@',currentNode)}} type="text" placeholder="点击按钮提示数据"></input><br/><br/>*/}
                        <input ref={this.seveInput} type="text" placeholder="点击按钮提示数据"></input>
                        <button onClick={this.showData}>点我提示左侧的数据</button>
                        <button onClick={this.changeWeather}>点我切换天气</button>
                    </div>
                )
            }
        }
        //渲染组件到页面
        ReactDOM.render(<Demo/>,document.getElementById('test1'))
    </script>
</body>
</html>